22 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Leaflets more than 5 in most of the leaves on each plant, but some of the leaves 

 occasionally of only 5 leaflets. 

 Plants trees; flowers pistillate and staminate, usually appearing before the 

 leaves, in small clusters or in panicles; fruit a winged samara. 



Fraxinus (p. 227). 

 Plants shrubs; flowers perfect, appearing after the leaves, in broad flat- topped 



cymes; fruit juicy, berry-like Sambucus (p. 261). 



Leaves alternate. 

 Stems armed with Bpines. 

 Plants trees; fruit a flat pod. 

 Leaves once pinnate; flowers very irregular, white or pinkish. Robinia (p. 185). 

 Leaves twice pinnate; flowers regular or nearly so, greenish. .Gleditsia (p. 180). 

 Plants shrubs; fruit not a flat pod. 

 Leaflets numerous; flowers in umbels arranged in panicles; fruit a black juicy 



5-celled drupe ARALIACEAE (p. 215). 



Leaflets 3-9; flowers not in umbels; fruit red ROSACEAE (p. 173). 



Stems without spines. 

 Leaves of 3 or 5 digitate leaflets. 

 Leaflets 3 (sometimes only 1), entire; plants erect; flowers showy, yellow, irreg- 

 ular; fruit a dry po.d FABACEAE (p. 181). 



Leaflets 5, toothed; plants climbing by tendrils; flowers very small, greenish, 



regular; fruit a juicy black berry Parthenocissus (p. 201). 



Leaves pinnate, of 3 to many leaflets. 

 Leaflets entire, or with one or 2 teeth near the base, numerous. Trees; fruit 



winged SIMAROUBACEAE (p. 193). 



Leaflets with numerous fine or coarse teeth, or rarely entire, the leaflets then 

 only 3. 

 Plants trees; flowers in catkins; fruit a nut. Leaflets 5 or more, aromatic. 



JTJGLANDACEAE (p. 135). 

 Plants shrubs; flowers not in catkins; fruit not a nut. 

 Leaflets gland-dotted, 3, nearly entire; fruit winged; erect shrubs. 



Ptelea {p. 192). 

 Leaflets not gland-dotted, 3 to many, conspicuously toothed; fruit a dry or 

 slightly juicy drupe; erect or climbing shrubs. 



ANACARDIACEAE (p. 198). 



2. Leaves entire, toothed, or lobed, but never compound. 



A. LEAVES OPPOSITE. 



Plants parasitic upon the branches of trees. Leaves entire, thick and leathery. 



LORANTHACEAE (p. 143). 

 Plants not parasitic. 

 Mature leaves toothed or lobed. 

 Plants trees; fruit a double samara. Leaves lobed; flowers yellow, green, or red. 



ACERACEAE (p. 200). 



Plants shrubs; fruit never a samara. 



Flowers borne in the axils of the leaves; fruit dehiscent, deeply 3-5-lobed; 



flowers greenish or purplish. Leaves finely toothed. . .Euonymus (p. 199). 



Flowers borne at the ends of the branches; fruit a small many-seeded capsule or 



a 1-seeded fleshy drupe, not lobed; flowers white. 



Corolla of 4 distinct petals; fruit a many-seeded capsule; leaves cordate-ovate, 



finely toothed HYDRANGEACEAE (p. 172). 



Corolla of united petals; fruit a fleshy 1-seeded drupe; leaves various in outline, 

 often lobed CAPRIFOLIACEAE (p. 259). 



